How to export Blender model into Adobe After Effects?
After Effects is not a 3D program, therefore it can not import 3D objects by itself. There are 3rd party programs that can help import an OBJ file. One of the best is Element 3D by Video Copilot ($200). After Effects also comes with Cinema 4D lite which has built in pipeline for working with 3D. You could always export from Blender into Cinema 4D and then use the built in pipeline to get it into After Effects.  

Hope this helps.